#64279 - 03/14/07 10:52 AM
Re: HUM HELP
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Gunslinger
Registered: 01/23/07
Posts: 43
Loc: Richmond, VA
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Have you tried connecting them individually to the ground / neutral bar? Or a better question, how is your dedicated circuit grounded? Strait to the g / n bar, or tied in with the other stuff?
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Outlaw Audio 990 Outlaw Audio 2200 (5) Monitor Audio RS-6 Monitor Audio LCR Philips Ambilight 42" HD Plasma Project Debut III
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#64280 - 03/14/07 11:25 AM
Re: HUM HELP
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Gunslinger
Registered: 01/14/07
Posts: 215
Loc: Ontairo, Canada
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I haven't tried connecting the ground wires, of the lines in, directly to the ground/neutral bar because the lines in are all too short (the reason, I assume, the electrician did it the way he did).
I have a ground wire from the ground post of my amp, directly connected to the ground/neutral bar in the panel.
That buzzing door bell transformer shares power with the line, I think, for my audio room. Can this transformer cause dc on the ac line? This is absolutely new to me, these concepts.
thanks,
John
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#64281 - 03/14/07 01:19 PM
Re: HUM HELP
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Deputy Gunslinger
Registered: 03/14/07
Posts: 4
Loc: New Castle, IN
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DR_JB,
I read through the thread and a couple of things pop out:
You definitely need to determine if you have an adequate ground.
Also, the benefits of the UPS have not been clearly articulated. The PRIMARY reason to have a UPS on your audio/video system is to take whatever voltage that comes in and output it as a pure 120VAC sine wave. This gives your more available voltage because 120v it the RMS (essentially average) voltage. The actual peak to peak voltage is quite a bit higher. It can take in voltages as low as 86 volts and as high as 137 or so volts, again, outputting it as 120VAC. It also cleans out all line noise and spikes. It has really nothing to do with the issue of when the power goes out other than it protects your gear from the on/off/on/off etc as the power company tries to stablize power in an outage situation.
I have to tell you, I have 2 UPS' in my system. A 1500VA (900 watts) and a 3000VA (2200 watts). The big boy feeds my Outlaw 7125 and my Carver M1.0T. The other one feeds my Adcom GFA555 and the rest of the gear.
I have seen many benefits to having the UPS' in my rack. The first and foremost is it has added unbelievable punch to the low end in my system. My Adcom is in bridged mode (600watts) and drives two 12" subs. So I already had tremendous furniture vibrating low end. But when I hooked the amp up to the UPS, now I can feel the impact in my chest even at lower levels. The reason for this is again, more volts available to the amp because of the pure sine wave. Also, it tends to give you more available reserve for the amp to pull power from. Awesome power. The next benefit was a dramatic increase in imaging. For my mains I have the Martin Logan Aeon electrostactics that already have incredible imaging. But when I hooked the Carver amp and the rest of the gear up to the UPS, HOLY COW! The imaging was rock solid. Better depth. Better width. Increased resolution of the sonic field. WOW. The last benefit I noticed was on my Hitachi rear screen HDTV. The picture has less noise, deeper blacks. I was actually suprised to see the difference.
Everyone who spends the kind of money we do on gear should have one or more of these in their racks. Let me tell you this. Do NOT spend $2K on the high end Monster or similar units. Buy a reconditioned APC or similar rack mount unit that they sell for computer server rooms. You can get them in 120V or 208/240V units that will more than feed everything you need. The 1500VA unit is actually a CyberPower that I paid $200 for. The 3000VA is an APC that I paid $440.
Next to speakers, I would have to say that this is one of the best improvements I have heard in my system. I have tried high end speaker wire and interconnects which helped, but not as much as the UPS.
Good Luck.
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#64282 - 03/14/07 06:52 PM
Re: HUM HELP
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Desperado
Registered: 01/17/02
Posts: 380
Loc: South Weymouth, MA USA
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Sorry, I was sidetracked! The UPS I linked to was for informational purposes only. I'm sure you can find a less expensive unit.
AudioGuru66 is correct in what he says about what a UPS does. In audio you would be using it as a way to provide a clean, pure sine wave. It would clean any extraneous noise induced before the UPS. I'm not concerned about keeping the audio system running for just 5 minutes after power loss.
The transformer you are talking could be the culprit! It shouldn't be making the sound your saying it is. It might be time for a replacement. They are inexpensive and can be bought at Home Depot, or any hardware store. Shut the circuit breaker off and remove the wire feeding the transformer and see if this works.
That's exactly what the electrician did to the ground wires! So long as the connector is tight and the wires don't easily pull out of it, it should be fine.
As I'm typing a thought came into my head. In most panel installations in houses the grounds and the neutrals,(white wire), land on the same bus. This bus is supposed to have a green screw driven through it into the circuit breaker cabinet. If the ground wires are separate from the neutrals, then either the same screw is used or a wire jumping between the 2 connection points is required. The neutral and the ground in a panel MUST be attached!!!
If you take your meter and check the resistance between the neutral and ground it should read "0" Hope this helps. Jim
P.S. Be careful in the panel!!!!
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#64283 - 03/15/07 05:37 PM
Re: HUM HELP
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Gunslinger
Registered: 01/14/07
Posts: 215
Loc: Ontairo, Canada
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AudioGuru66, Thanks for the advice. Tomorrow, I will work through the power panel and check for all these weaknesses, including the ground and buzzing transformer. And, thank you for the detailed explanation, regarding the use of a UPS. These things are quite the machines, weighing in at 50/60 lbs. You are right, I did not understand. Is this the type of UPS that you have: http://cgi.ebay.ca/APC-Smart-UPS-3000-Ra...1QQcmdZViewItem and, if so, what do you think of this one? Hullguy, No need to apologize; I understand we all need to live our lives. I do appreciate your guidance, however. Tomorrow I will work through the power panel and check for all the points you've made reference to. I need also to distinguish the individual circuits, given that last night, when I turned on the amp, all the lights in the kitchen dimmed (which is not good, as I thought it was a separate circuit). My kitchen has two new dimmer switches, Divas, and, the electric stove, the motor/compressor in the fridge (not the best circuit for my amp). I'm going to pull the transformer for the doorbell and see if it makes a difference and, I will also replace it, purchase another, next time I'm at Home Depot. Thanks for the detailed explanation. I will be careful, will use latex gloves. That APC 3000v unit seems about right, as when I added all my av components together, it worked out to 30amps. But, gee, this ebay APC unit is huge, bigger than my 1900 watt amplifier! I think it weighs nearly 60 lbs. The other worry is that while I'm looking to achieve clean power for my AV equipment and eliminate toroidal hum (primarily because it bugs me), the APC could be counter productive as I understand it has two 5", internal computer fans! Gee, I could end up with more, rather than less, noise! lol Am I right about this? I certainly appreciate your guidance & thank you! Sincerely, John P.s. ... it's nice to be learning new stuff.
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#64284 - 03/15/07 06:48 PM
Re: HUM HELP
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Gunslinger
Registered: 01/14/07
Posts: 215
Loc: Ontairo, Canada
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Here are the specs for the unit: http://www.apcc.com/resource/include/techspec_index.cfm?base_sku=SU3000RMJ3U Is this a good one? I was wrong about the weight, it's not 60lbs, it's 75lbs and that's without the batteries. The specs say: Audible noise at 1 meter from surface of unit 47 dBA I don't know how to measure the noise of my toroidal hum, but I'm guessing it's less than this. John
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#64285 - 03/16/07 07:20 AM
Re: HUM HELP
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Desperado
Registered: 01/17/02
Posts: 380
Loc: South Weymouth, MA USA
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Dimmer switches are known to be "dirty" in reqards to induced noise on circuits.
If you can place the ups in a remote location, in the cellar or attic, the noise from the fans becomes a non-issue. I placed all of my amps in the cellar. This APC unit seems fine, it provides plenty of power. Jim
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#64286 - 03/16/07 10:07 AM
Re: HUM HELP
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Gunslinger
Registered: 01/12/06
Posts: 33
Loc: Syracuse
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hello ALL
I want to buy one of those UPS thingy's (hahaha) but not sure what to look for mostly i like the regulated power and am not to concerned with having short term power when the power goes out do i just add the wattage of my equipment and buy like that ????
THANKS AGAIN Supertom
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#64287 - 03/16/07 11:10 AM
Re: HUM HELP
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Gunslinger
Registered: 01/14/07
Posts: 215
Loc: Ontairo, Canada
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Hullguy,
having this UPS in the basement would make the installation far more complex, as an oak covered floor would divide the system from the power source. A single power cable I can get through the floor, but not several speaker wires, or several power cables.
That thing is monsterous in size ... 25" deep and 70lbs, without the batteries. My room is not big and this will add more noise. It may be ideal for some, but not, I think, for my circumstances.
In terms of a practical application, I think the Surge-X is probably the way to go. I'll include an AV installers opinion on all this, in the next message.
thanks!
John
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#64288 - 03/16/07 11:15 AM
Re: HUM HELP
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Gunslinger
Registered: 01/14/07
Posts: 215
Loc: Ontairo, Canada
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John,
Yes, UPS systems do clean up the power very well when converting AC to DC then back again, but again most filtration systems on good surge/spike protection system will do the same thing, except that the UPS is louder (as you noted).
In regards to providing a constant 120VAC to an amplifier, this would be a valid point if the amplifier used a regulated power supply that is fixed @ 120VAC. However, almost all power supplies for amplifiers use transformers that have multiple taps on them that will draw current based upon what the incoming voltage is (usually between 100VAC & 125VAC).
The problem with hooking up a good amplifier to a UPS is that unless the UPS is capable of allowing sufficient current draw through it (in large bursts), the amplifier will react just like it does without a UPS. Remember, these UPS systems are not car batteries nor do they have capacitors to allow quick discharges of large current without effecting other systems.
Also, most high capacity UPS systems don’t have great surge/spike protection. The APC 3000VAC unit has good, but not great protection and is not impervious to lightning.
In the end, unless your voltage is down around 100 to 107 volts ac, then I would stick with an item like the Surge-X.
There are other items to discuss in regards to the above, but on a side note I have a friend who designs amplifiers for a major electronics company and his golden rule is to always allow amplifiers to run with as little resistance between them and the power grid, placing a UPS in between the two is just not something he would ever do (and he has tested this with bench equpment).
Feel free to ask any other questions if you like.
Regards,
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